Getting information from previous accountants

I have taken on a sole trader client whose previous accountant is ignoring emails and failing to pass on information in particular relating to balance sheet items.

I suspect that he does not have working papers to back up the figures but I don't know. I do not know if he has a professional body.  He did not prepare accounts with an accountants report, just a profit and loss and balance sheet so I do not have letters after his name to look for.  He does not have a website or linkedin page.

I have an address, email and telephone but I only get sporadic responses and he seems to spend a lot of time abroad.

Does anyone have ideas on how to deal with this?

Firstly I am interested in ideas about how to get the information.

Secondly I am interested to know at what point I give up and recreate this year's accounts with the information I have got.

Many thanks